Friday, November 11, 2011

Once the small pixel world switched to BSI, one might think that metal shifts across the pixel array is a thing of the FSI past. However, Omnivision's patent application US20110266421 "Image sensor having metal reflectors with scaled widths" brings it to BSI realm. The company proposes to scale metal reflectors 122-140 across the pixel array to reduce the optical crosstalk on the array edges and in the corners:

Microlens and color filters are shifted too - this is easy and done by everybody. Shifting metals is more tricky and often involves complex CAD scripts transforming the pixel layout from the center to the edges and then to the corners.

Omnivision patent application just talks about metal width scaling - this should be easy to implement.

Maybe. It probably wouldn't work well if there were a lot of additional NIR sources or reflectors. Think road cat-eyes, bicycle reflectors, or reflective signs in the day time as opposed to at night.

Besides which, if it did turn out to be a covert-camera detection technique, there'd probably be US $500 million of research money covertly invested in covert-camera-detection prevention, counter cover-camera-detection prevention, etc.